I agree with everyone (even Zach) suggesting you need to eat more. Eat at least BMR most days. Use fasting strategically to lower fat on occasion but make sure you still dial in calories weekly. Remember, if you needed 2,000 calories to maintain daily, then you need 14,000 calories a week. It doesn't really matter if you eat a strict 2,000 every day, but make sure you make up for fasting days by consuming even more on other days.
I would recommend two days (not necessarily in a row) of strict fasting per week, then making sure to make up the missed calories on those days by eating more throughout the rest of the week.
However, it is rediculous to suggest that low carb caused your insulin issues. Low carb CAN cause insulin resistance when first starting out because your body needs time to adjust to a new way of eating, but that's only natural. Your body needs to adjust to anything new. After sticking to it for a while your body gets used to operating on the lower insulin levels and even ketones (if you go that low), and you can run just fine.
However, in your case, you might have pushed the ketosis thing too fast. I would concentrate on low carb eating and getting lots of primal-approved exercise such as bodyweight work, lifting heavy things, and some moderate cardio into your routine. I wouldn't stress the daily weigh-ins, the protein counting, the fat content of your foods, at least, not until you have reversed your insulin issues.
BECAUSE you have insulin issues, you might not be reaping all of the benefits that you otherwise might from being in ketosis. Work on the most important issues you have first (getting back to the basics to deal with your insulin problems) and THEN bring in some more advanced techniques (such as ketosis) to support your health once you have delt with the main issues.